“We believe a prolonged period of deleveraging in the U.S., coupled with an uneven global recovery, are just two of the reasons why this could prove to be the longest US expansion — ever,” Parker wrote.

RBC Capital Markets’ Jonathan Golub shared a similar sentiment in a research note publish around the same time as Parker’s.

“Earnings projections for 2015 — 16 have been rising since April, reversing a downward trend,” Golub wrote. “We believe this reflects growing optimism (especially among CEOs via stronger guidance) on the direction of the economy. Given a lower cost of capital and enhanced growth prospects, we see further upside to stocks over the next several years.”

Years.

These bold predictions aren’t without some historical precedent.

In his note, Golub presented a 100-year long chart of the Dow Jones Industrial Average on a log scale. As you can see, the stock market has actually experienced long periods of volatile sideways moves before shooting higher.

“As the super cycle chart shows, it is not unusual for the market to experience prolonged periods of strong returns,” Golub said.

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